The present invention relates generally to the field of shared computer communications and computer conferencing. In particular, one embodiment of a conferencing system according to the present invention facilitates the conferencing of two or more persons, each with a computer at one or more locations with a shared visual display and additional communication capabilities such as video, shared drawing, audio, text chat, etc. and facilitates the recording and later playback of the communications.
Existing conferencing systems can be described as either video conferencing systems or “whiteboard” systems. In a video conferencing system, a snap-shot of the conference presentation is taken at regular intervals, such as thirty times per second. Given that the image on a computer display is not changing nearly that often, video conferencing wastes large amounts of bandwidth. In a whiteboard system, the presenter at the conference draws within a whiteboard application or imports the output of another program into the whiteboard program for manipulation. When the presenter is ready to present a snap-shot, the presenter presses a “send” button and the whiteboard program updates all the attendees' displays with the image created by the presenter. This type of system, while requiring less bandwidth than video conferencing, is clumsy to use, lacks real-time responses, and limits the presenter to the tools provided with the whiteboard program.
Existing shared-display or shared-image systems rely on interception and communication of display or graphics system commands or depend on conferees' having similar hardware and software platforms. These systems lack flexibility and performance if the network connections are unreliable or have narrow bandwidth, or they require uniform hardware or software installations.
Existing systems that provide single or multiple data stream handling of a nature different than shared-image conferencing depend on wide bandwidth network connections or on all participants having similar platforms.